In an LTE (Long Term Evolution) mobile communication system, a mobile station (UE: User Equipment) controls transmission power of a PUSCH (Physical Uplink Shared Channel) or a PUCCH (Physical Uplink Control Channel) according to a TPC (Transmission Power Control) command from a base station (eNB: evolved Node B).
For example, when a base station receives from a mobile station a buffer status report indicating that there are uplink (UL) transmission data to be transmitted from the mobile station, the base station allocates PUSCH transmission to the mobile station by a scheduler and transmits an UL scheduling grant on a PDCCH (Physical Downlink Control Channel). A TPC command for the PUSCH is transmitted along with the UL scheduling grant. A TPC command for the PUSCH is defined in Table 5.1.1.1-2 and Table 5.1.1.1-3 in TS 36.213 (see 3GPP TS 36.213, V10.6.0 (2012-06)).
When the base station has downlink (DL) data to be transmitted to a mobile station, the base station allocates PDSCH (Physical Downlink Shared Channel) transmission to the mobile station by the scheduler and transmits DL scheduling information on the PDCCH. A TPC command for the PUCCH is transmitted along with the DL scheduling information. A TPC command for the PUCCH is defined in Table 5.1.2.1-1 and Table 5.1.2.1-2 in TS 36.213 (see 3GPP TS 36.213, V10.6.0 (2012-06)).